You are right. Because of the constrains the RegisterCallback has it is not handled correctly and an error is poped. I will need to correct this. For a quickfix however, you can open up ReflectedMethodNodeWrapper.cs file and comment lines #57 to #61 in the SetMethod method. Doing this will allow you to add the RegisterCallback method node. Just remember to right click on it once it is added and from the menu select “Change Generic Type” (to MouseDownEvent in this case).
Gavalakis
